1. Field
The present invention relates generally to liquid dispensers, such as water dispensers, which control the temperature of a liquid to be dispensed from the dispenser, and also relates to liquid containers to be used in such liquid dispensers. The present invention also relates to liquid containers.
2. State of the Art
There are numerous types of liquid containers such as bottles, cans, and plastic containers. Where it is desired to maintain liquid in such liquid containers at a particular temperature, the containers are usually placed in a temperature controlled space where the temperature of the container and the liquid contents of the container are allowed to equilibrate with the temperature in the temperature controlled space. For example, to keep the liquid contents of a container cool, the container is placed in a storage space which is cooled to a particular temperature, such as being placed in a refrigerator. A bottle, carton, or plastic container of milk can be placed in a refrigerator to keep the milk in the container cool. A bottle, pitcher, plastic container, or can of water or soft drink can be placed in a refrigerator to cool the drink before it is used. When placed in a controlled temperature space, such as in a refrigerator, the container is cooled and the contents of the container is cooled through the container. The speed with which the liquid in the container is cooled depends in large part upon the heat transfer properties of the container and the temperature of the temperature controlled space, such as the interior space of the refrigerator.
Liquid dispensers are common and take many forms. Portable drink containers such as insulated containers are designed to hold hot or cold liquids and to keep such liquids hot or cold for extended periods of time because the containers are made of materials with low heat conductivity. The temperature of the liquid in the container at any given time is determined by the temperature of the liquid when put into the container, how long the liquid has been in the container, the heat conductivity of the container, and the ambient temperature of the surroundings of the container. Sometimes a liquid to be cooled is placed in an insulated container with ice cubes to cool and maintain the liquid cool for an extended period. Liquid dispensers, such as plastic containers sized to fit into a refrigerator and having a dispensing valve therein, are available which sit in a refrigerator to keep the liquid contents of the dispenser cool. When it is desired to dispense the cooled liquid, the refrigerator is opened and the cool liquid is dispensed through the dispensing valve. These are similar to other plastic containers, such as plastic milk or water containers or bottles, which are placed in a refrigerator to keep the contents of the containers cool.
Some liquid dispensers, such as office water coolers, use a water container, such as a five gallon glass or plastic water bottle that is inverted on the water cooler so that water can flow by gravity from the container into the water cooler which includes a cool water reservoir into which water flows and is cooled. Some water coolers also have a hot water reservoir where, again, water flows by gravity from the water container into the hot water reservoir where it is heated. The cooled or heated water is dispensed from the respective reservoirs through valves which are operated to dispense the cooled or heated water. The reservoirs have limited capacity, such as about one and one half quart. When water is dispensed from a reservoir, additional water flows from the water container into the reservoir from which the water was dispensed, and this additional water which is at ambient temperature, heats or cools the water in the reservoir. The water then in the reservoir is heated or cooled in the reservoir over time to the desired temperature. Thus, only a limited amount of cooled or heated water of the desired temperature is available at any time. The entire water container, such as the five gallon water bottle, and its liquid contents is not cooled or heated.
Bag-in-box container systems have become widely used as packing and shipping containers for a variety of liquid products such as soft drink syrup, milk, and wine. Such systems generally include a flexible bag or bladder disposed in a cardboard box such as a corrugated cardboard box. The flexible bladder can conform to the shape of the inside of the box when filled with a liquid material. However, the bag does not provide a shape retaining container and the box is needed to provide structure and shape to the container. The box provides a fixed container shape for the bag and contents and protects the bag. It will be appreciated that the box shape of the container has particular advantages for stacking the containers and maximizes the number of containers that can be stored within a given storage space. Additionally, such bag-in-box containers are usually relatively inexpensive to make and easy to produce and assemble. Therefore, the bag-in-box container is usually disposable and is disposed of after use rather than being saved and refilled. Bag-in-box containers come in various sizes, with many such containers having a five gallon capacity similar to the five gallon office water cooler bottles, two and one half gallon sizes are common, with bag-in-box wine containers generally having about a five liter capacity (about one and one-quarter to one and one-half gallon) capacity.
Sometimes products stored, transported, and dispensed from bag-in-box containers need to be cooled and maintained in cooled condition. For example, bag-in-box containers of milk are stored and transported in a refrigerated space and the dispenser for the milk from the bag-in-box containers includes a refrigerated space to hold and refrigerate the box with the bag therein. The cool of the refrigerated space penetrates through the box and cools the bag and the milk therein. These bag-in-box milk containers are constantly maintained in a cooled condition from filling to dispensing so that the milk is maintained and is dispensed from the bag-in-box container in cooled condition. However, with bag-in-box containers, the cardboard forming the box for the bag-in-box containers generally has poor heat conduction properties so provides relatively poor heat conduction between the bag and the environment outside the box. This is not a problem where the containers are continuously maintained in a refrigerated environment, and can even be an advantage in slowing warming of the contents of the container if the container is temporarily removed from the refrigerated environment. But, if the bag-in-box container is stored at ambient temperature and it is desired to cool the contents of the bag-in-box container prior to use, the bag-in-box container has to be placed in a refrigerated environment for a period of time prior to use sufficient to allow cooling of the contents through the box. For example, bag-in-box wine containers can be stored and transported at ambient temperature. Where the wine is desired to be cooled prior to serving, the bag-in-box wine container is placed in a refrigerator for a time period prior to serving sufficient to cool the wine through the box. Planning is needed to place the bag-in-box container in the refrigerator enough time prior to serving to allow it to cool sufficiently. Again, once the wine in the bag-in-box container is cool, the cardboard box holding the bag provides insulation to keep the wine cool for a period of use with the container out of the refrigerator.
Water is sometimes packaged in a bag-in-box container as shown in my U.S. Pat. No. 6,926,170. As shown in that patent, the water is stored and used at ambient temperature. The water from the bag-in-box container is pumped from the bag-in-box container to a drink machine using water, or to a water cooling or a water heating system when it is desired to supply either cold or hot water. The water cooling or water heating system may be similar to water cooling and heating systems used in the usual office water cooler using inverted five gallon bottles of water as the water supply as described above. With such systems, only a small portion of water from the bag-in-box water supply is cooled at any one time in a water cooling reservoir. As cooled water is used, ambient temperature water is pumped to the cooling reservoir from the bag-in-box water supply. The amount of cooled water available at any one time is limited to somewhat less than the capacity of the cooling system reservoir as ambient temperature water is added to the cooled water in the reservoir as the cooled water is dispensed. U.S. Pat. No. 6,143,258 shows a water dispenser, again similar to a water dispenser using a five gallon bottled water supply, but which uses a bag-in-box water supply rather than a bottled water supply. The water dispenser of this U.S. Pat. No. 6,143,258 similarly has a reservoir for cooled water and a reservoir for hot water. Water flows by gravity from the bag-in-box supply at ambient temperature into the cool water reservoir to be cooled or into the hot water reservoir to be heated. Again, as with the standard five gallon bottle water coolers, only a small portion of water from the bag-in-box water supply is cooled at any one time in the water cooling reservoir. As cooled water is used, ambient temperature water flows by gravity to the cooling reservoir from the bag-in-box water supply. If it is desired to cool and have available the entire supply of water in a bag-in-box container of water, it is necessary to place the bag-in-box water container in a refrigerator for a time period sufficient to cool the water therein. This can be a slow process because the cooling has to take place through the box of the bag-in-box container. Relatively fast cooling of the water is not achieved.
Even where a liquid container such as a plastic container forming a liquid dispenser is placed in a refrigerator, or a glass or plastic bottle such as a gallon milk container or other drink container is placed in a cooled location, such as in a refrigerator, significant time is required for heat to be transferred from the liquid in the container, through the container, to the cooled air in the refrigerator.